Boeing NKC-135A Airborne Laser Lab

While the KC-135A was usually used for in-flight refueling, the Airborne Laser Lab was a modified version used for flight testing. Similar to the commercial Boeing 707, the slightly smaller KC-135 was designed to military specifications and operated at high gross weights. The KC-135A's initial flight occurred on Aug. 31, 1956, and the USAF accepted its first one on Jan. 31, 1957. By 1966, 732 KC-135As had been built, and the aircraft had become the USAF's standard tanker. It was also used for transporting cargo or personnel and by 1970 was serving in other roles, including reconnaissance, electronic intelligence and project testing.

The NKC-135A on display is one of 14 KC-135As permanently converted for special testing. It was extensively modified by the Air Force weapons Laboratory at Kirtland Air Force Base, N.M., and used in an 11-year experiment to prove a high-energy laser could be operated in an aircraft and employed against airborne targets. During the experiment, the Airborne Laser Lab destroyed five AIM-9 Sidewinder air-to-air missiles and a Navy BQM-34A target drone.